Blood of Bahamut is set in the world of Altail, the people of this world reside in countries that they’ve built on the back of long sleeping giants who are considered both their homes and their gods.

All peace is lost when the giants awaken and grow violent. Thinking that they’ve been forsaken by their gods, people begin to flee their towns. At this time, seven warriors rise to restore the peace, two of which have been revealed so far:

• Ibuki is an eighteen-year-old male sword wielder of the Gigant race.
• Yui is a seventeen year old female Gigant who wields a staff.

The race of the two heroes is named after the beast on whose back they reside, in their case Gigant, a colossus that will span both screens of the DS. Standing off in the distance, the giant attacks with direct fist attacks, and also with lasers. Gigant is just one of a variety of giants against whom players will face off. The giants have different forms, some not looking quite as human as Gigant. The only common point between all the beasts is that they’re huge and have vast power. Normal attacks don’t work against them. However, they do have weak points which can be attacked for massive damage.

By attacking certain parts repeatedly, certain parts of the giants will fall off, making them weaker, a technique that you will have to use frequently to reveal the giant's weak spot.

Blood of Bahamut will offer over 130 missions of a variety of difficulty levels, reaching beginners and experts. Players face off against the giants in two main types of missions: main story missions and free play missions. The free missions feature giants of different shape and form from those of the main story missions.

All missions, both free and story, are playable in multiplayer by up to four players, suggesting that some beasts will require multiple players using techinques such as having one player draw the beast’s attention while others attack it from the back.